# Lucas' square pyramid problem revisited

@article{Bennett2002LucasSP, title={Lucas' square pyramid problem revisited}, author={Michael A. Bennett}, journal={Acta Arithmetica}, year={2002}, volume={105}, pages={341-347} }

are given by (s, t) = (1, 1) and (24, 70). Putative solutions by Moret-Blanc [30] and Lucas [25] contain fatal flaws (see e.g. [39] for details) and it was not until 1918 that Watson [39] was able to completely solve equation (1.1). His proof depends upon properties of elliptic functions of modulus 1/ √ 2 and arguably lacks the simplicity one might desire. A second, more algebraic proof was found in 1952 by Ljunggren [23], though it also is somewhat on the complicated side. Attempts to repair… Expand

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